J. Liu et al. / Tetrahedron Letters 47 (2006) 6121–6123
6123
23
in hexanes]; ½aꢂD 36.6 [c = 0.89, CH2Cl2]; 1H NMR
2H), 9.75 (dd, J = 2.0 and 3.5 Hz, 1H); 13C NMR
(125 MHz, CDCl3): d 14.2, 40.5, 45.4, 55.5, 71.7, 114.0,
115.9, 129.6, 130.5, 139.9, 159.5, 202.0; IR (neat) cmꢀ1
2967m, 2836m, 1722s, 1512s, 1060s, 918s. Compound 14:
For the major isomer: Rf = 0.65 [30% EtOAc in hexanes]; 1H
NMR (500 MHz, CDCl3): d 0.082 (s, 3H), 0.107 (s, 3H),
0.90 (s, 9H), 0.99 (d, J = 7.0 Hz, 3H), 1.19 (s, 9H), 1.20–
1.23 (m, 2H), 1.44 (dt, J = 3.0, 9.5 Hz, 2H), 1.49–1.61 (m,
4H), 1.74 (dd, J = 2.0, 13.0 Hz, 2H), 1.82–1.85 (m, 1H),
2.37–2.46 (m, 2H), 2.58–2.61 (m, 1H), 2.66 (dd, J = 8.0,
15.0 Hz, 1H), 3.38–3.42 (m, 1H), 3.75–3.80 (m, 1H), 3.94
(ddd, J = 4.0, 4.0, 8.0 Hz, 1H), 4.10 (ddd, J = 6.0, 11.0,
11.0 Hz, 1H), 4.13 (ddd, J = 7.0, 10.5, 10.5 Hz, 1H), 4.23
(ddd, J = 4.0, 8.0, 12.5 Hz, 1H), 5.01 (d, J = 9.0 Hz, 1H),
5.02 (d, J = 18.0 Hz, 1H), 5.77 (ddd, J = 7.0, 10.0, 17.0 Hz,
1H); mass spectrum (APCI): m/e (% relative intensity)
535.5 (M+Na)+ (100). Compound 15: For the major isomer:
Rf = 0.20 [25% EtOAc/hexane]; 1H NMR (500 MHz,
CDCl3): d 1.03 (d, J = 7.0 Hz, 3H), 1.19 (s, 9H), 1.20–
1.32 (m, 2H), 1.48–1.61 (m, 6H), 1.73 (q, J = 6.5, 13.0 Hz,
2H), 1.82–1.84 (m, 1H), 2.38 (dd, J = 5.0, 15.0 Hz, 2H),
2.54–2.57 (m, 1H), 2.57 (m, 2H), 2.64 (dd, J = 8.0, 15.0 Hz,
1H), 3.26 (d, J = 3.5 Hz, 1H), 3.39 (dddd, J = 1.0, 6.5, 6.5,
12.5 Hz, 1H), 3.69 (dddd, J = 1.5, 4.0, 4.0, 8.0 Hz, 1H), 3.75
(m, 1H), 4.11 (ddd, J = 7.0, 7.0, 12.5 Hz, 2H), 4.26 (m, 1H),
4.51 (d, J = 10.5 Hz, 1H), 4.58 (d, J = 10.5 Hz, 1H), 5.05
(ddd, J = 1.5, 1.5, 7.5 Hz, 1H), 5.06 (ddd, J = 1.5, 1.5,
17.5 Hz, 1H), 5.81 (ddd, J = 7.5, 10.5, 17.5 Hz, 1H), 6.87
(d, J = 9.0 Hz, 2H), 7.28 (d, J = 8.5 Hz, 2H); 13C NMR
(125 MHz, CDCl3): d 18.1, 27.5, 31.3, 31.3, 31.3, 35.2, 35.4,
39.4, 41.5, 42.8, 44.4, 54.1, 55.2, 59.4, 65.0, 68.8, 76.2, 78.4,
78.7, 83.0, 117.9, 117.9, 118.8, 133.6, 133.6, 135.0, 144.8,
163.3, 182.6, 214.4; IR (neat) cmꢀ1 3871m, 3751m, 3677m,
3651m, 3494br s, 2956s, 2936s, 2870s, 2342s, 1719s, 1702s,
1616s; mass spectrum (MALDI): m/e (% relative intensity)
541 (M+Na+) (100), 518 (M+) (4), 409 (4), 321 (10), 273
(39).
(500 MHz, CDCl3): d 1.54–1.65 (m, 2H), 1.61–1.69 (m,
1H), 1.86 (br s, 1H), 2.91 (dt, J = 4.0, 2.5 Hz, 1H), 3.50 (dt,
J = 2.5, 5.5 Hz, 1H), 3.49 (t, J = 6.5 Hz, 2H), 3.62 (ddd,
J = 4.5, 7.0, 11.5 Hz, 1H), 3.89 (ddd, J = 2.5, 5.5, 13.0 Hz,
1H), 4.51 (s, 2H), 7.28–7.30 (m, 1H), 7.30–7.35 (m, 4H); 13
C
NMR (125 MHz, CDCl3): d 22.7, 29.5, 31.4, 56.0, 58.7,
61.9, 70.1, 72.9, 127.6, 127.7, 128.4, 138.5; IR (neat) cmꢀ1
3434br s, 3030m, 2936s, 2861m, 1100s; mass spectrum
(APCI): m/e (% relative intensity) 237.2 (M+H)+ (100).
Compound 7: Rf = 0.35 [17% EtOAc/hexane]; 1H NMR
(400 MHz, CDCl3): d 1.38 (s, 3H), 1.38–1.43 (m, 2H), 1.44
(s, 3H), 1.46–1.58 (m, 4H), 1.63 (tt, J = 6.8, 6.8 Hz, 2H),
3.47 (t, J = 6.8 Hz, 2H), 3.82 (ddd, J = 1.6, 5.2, 12.0 Hz,
2H), 3.95 (td, J = 2.8, 12.4 Hz, 1H), 4.54 (s, 2H), 7.26–7.37
(m, 5H); 13C NMR (125 MHz, CDCl3): d 19.5, 21.8, 29.9,
30.3, 31.5, 36.5, 60.3, 69.0, 70.5, 73.1, 98.4, 127.7, 127.9,
127.9, 128.6, 128.6, 138.9; IR (neat) cmꢀ1 2992s, 2940s,
2862s, 2360s. Compound 8: Rf = 0.45 [33% EtOAc/hex-
ane]; 1H NMR (400 MHz, CDCl3): d 1.38 (s, 3H), 1.39–1.44
(m, 1H), 1.45 (s, 3H), 1.47–1.83 (m, 5H), 2.46 (td, J = 1.6,
6.4 Hz, 2H), 3.81–3.88 (m, 2H), 3.93–3.99 (td, J = 2.8,
12.0 Hz, 1H), 9.77 (t, J = 1.6 Hz, 1H); 13C NMR
(125 MHz, CDCl3): d 18.0, 19.5, 30.2, 31.5, 36.0, 44.0,
60.2, 68.8, 98.5, 202.8; IR (neat) cmꢀ1 3300m, 2993s, 2938s,
2869s, 1718s. Compound 10: Rf = 0.33 [67% EtOAc/
hexane]; 1H NMR (400 MHz, CDCl3): d 1.17–1.35 (m,
2H), 1.51–1.65 (m, 3H), 1.66–1.76 (m, 1H), 1.81–1.87 (m.
1H), 2.16 (s, 3H), 2.47 (dd, J = 4.8, 16.0 Hz, 1H), 2.57 (br s,
1H), 2.67 (dd, J = 7.6, 16.0 Hz, 1H), 3.60 (dddd, J = 2.0,
3.6, 8.4, 12.8 Hz, 1H), 3.76 (dt, J = 5.6, 5.6 Hz, 2H), 3.83
(dddd, J = 2.0, 4.8, 8.0, 12.8 Hz, 1H); 13C NMR (125 MHz,
CDCl3): d 23.5, 31.1, 31.3, 31.4, 38.2, 50.3, 61.5, 74.2, 78.5,
207.5; IR (neat) cmꢀ1; 3852m, 3675m, 3649m, 3629m,
3376br s, 2934s, 2860s, 2340s, 1716s, 1670s; mass spectrum
(APCI): m/e (% relative intensity) 187 (M+H, 100), 169
(24), 151(27), 129(84), 111(18). Compound 11: Rf = 0.40
[25% EtOAc/hexane]; 1H NMR (400 MHz, CDCl3): d 1.19
(s, 9H), 1.53–1.63 (m, 2H), 1.53–1.63 (m, 3H), 1.75 (dd,
J = 7.0, 13.0 Hz), 1.82–1.85 (m, 1H), 2.18 (s, 3H), 2.41 (dd,
J = 5.0, 15.0 Hz, 1H), 2.66 (dd, J = 7.5, 15.0 Hz, 1H), 3.42
(dddd, J = 1.5, 7.0, 10.5, 13.0 Hz, 1H), 3.75 (dddd, J = 2.0,
5.0, 8.0, 11.0 Hz, 1H), 4.12 (ddd, J = 6.0, 10.5, 11.0 Hz,
2H); 13C NMR (125 MHz, CDCl3): d 23.7, 27.4, 27.4, 27.4,
31.2, 31.5, 31.6, 35.6, 39.0, 50.6, 61.3, 74.7, 74.8, 178.7,
207.8; IR (neat) cmꢀ1 3420br s, 2929s, 2857s, 2360s, 2341s
1710s; mass spectrum (APCI): m/e (% relative intensity) 293
(M+Na+) (14), 271 (M+H) (100), 253 (71), 213 (85), 169
(50), 151 (89), 133 (19), 129 (6), 111 (42). Compound 12:
˜
8. (a) Omura, K.; Swern, D. Tetrahedron 1978, 24, 1651; (b)
Mancuso, A. J.; Swern, D. Synthesis 1981, 165.
9. Wadsworth, W. S. Org. React. 1977, 25, 73.
10. Katsuki, T.; Sharpless, K. B. J. Am. Chem. Soc. 1980, 102,
5974.
11. For a review on Sharpless asymmetric epoxidation:
Finn, M. G.; Sharpless, K. B. In Asymmetric Synthesis;
Morrison, J. D., Ed.; Academic Press: New York, 1985;
Vol. 5, p 247.
12. The enantiomeric excess was determined by chiral HPLC:
the retention times of the two enantiomers were 25.789 (S)
min and 27.861 (R) min, respectively. The formation of
R-(+)-Mosher’s ester gave P 95% de by NMR.
13. Parikh, J. R.; von E. Doering, W. J. Am. Chem. Soc. 1967,
89, 5505.
14. For the synthesis of key precursor to 12a, see: (a)
Zampella, A.; Sepe, V.; D’Orsi, R.; Bifulco, G.; Bassarello,
C.; D’Auria, M. V. Tetrahedron: Asymmetry 2003, 14,
1787; (b) Brown, H. C.; Bhat, K. S. J. Am. Chem. Soc.
1986, 108, 5919.
15. For the synthesis of key precursor to 12b, see: Drouet, K.
E.; Theodorakis, E. A. Chem. Eur. J. 2000, 6, 1987.
16. Mukaiyama, T.; Banno, K.; Naraska, K. J. Am. Chem.
Soc. 1974, 96, 7503.
17. (a) Evans, D. A.; Dart, M. J.; Duffy, J. L.; Yang, M. G.;
Livingston, A. B. J. Am. Chem. Soc. 1995, 117, 6619; (b)
Evans, D. A.; Dart, M. J.; Duffy, J. L.; Yang, M. G. J.
Am. Chem. Soc. 1996, 118, 4322; (c) Evans, D. A.; Duffy,
J. D.; Dart, M. J. Tetrahedron Lett. 1994, 35, 8537.
18. (a) Evans, D. A.; Bartroli, J.; Shih, T. L. J. Am. Chem.
Soc. 1981, 103, 2127; (b) Evans, D. A.; Vogel, E.; Nelson,
J. V. J. Am. Chem. Soc. 1979, 101, 6120.
23
Rf = 0.80 [30% EtOAc in hexanes]; ½aꢂD 4.35 [c 0.96,
CHCl3]; 1H NMR (500 MHz, CDCl3): d 0.040 (s, 3H),
0.052 (s, 3H), 0.89 (s, 9H), 1.00 (d, J = 7.0 Hz, 3H), 1.62–
1.72 (m, 2H), 2.29 (dddd, J = 4.0, 7.0, 7.0, 14.0 Hz, 1H),
3.45–3.51 (m, 2H), 3.77 (ddd, J = 4.0, 7.5, 7.5 Hz, 1H), 3.81
(s, 3H), 4.39 (d, J = 11.5 Hz, 1H), 4.44 (d, J = 11.5 Hz,
1H), 4.98 (d, J = 18.0 Hz, 1H), 5.00 (d, J = 10.0 Hz, 1H),
5.77 (ddd, J = 7.5, 11.0, 16.5 Hz, 1H), 6.88 (d, J = 8.5 Hz,
2H), 7.26 (d, J = 8.5 Hz, 2H); 13C NMR (125 MHz,
CDCl3): d ꢀ4.51, ꢀ4.37, 14.6, 25.9, 33.3, 43.5, 55.3, 67.1,
72.6, 113.6, 114.6, 129.3, 130.7, 140.7, 159.1; IR (neat) cmꢀ1
3071w, 2953s, 2856m, 1513m, 1520s. Compound 13:
23
Rf = 0.65 (33% EtOAc in hexane); ½aꢂD +19.3 [c 0.49,
CH2Cl2]; 1H NMR (500 MHz, CDCl3):
d 1.06 (d,
J = 7.5 Hz, 3H), 2.45 (ddd, J = 3.5, 4.5, and 16.5 Hz,
1H), 2.50–2.54 (m, 2H), 3.80 (s, 3H), 3.95 (dt, J = 4.5 and
6.5 Hz, 1H), 4.45 (d, J = 11.0 Hz, 1H), 4.53 (d, J = 11.0 Hz,
1H), 5.07 (ddd, J = 1.5, 1.5, and 17.0 Hz, 1H), 5.08 (ddd,
J = 1.5, 1.5, and 10.5 Hz, 1H), 5.77 (ddd, J = 7.0, 10.5, and
17.0 Hz, 1H), 6.87 (d, J = 9.0 Hz, 2H), 7.24 (d, J = 9.0 Hz,